I ran into an issue this past week, where VirtualCenter wouldn’t start.  I was swamped with some other issues so in my haste made a few bad decisions that made everything worse and eventually discovered the root of the issue: the SQL logfile was full.  I changed it to unrestricted growth and voila we were back in business. 

Wait, no we weren’t!  None of the cluster hosts would enable HA, they errored out, all of them.  I tried several things that were suggested at The VMWare Communities without success, from removing the hosts from the cluster and re-adding them, to just disabling HA and enabling it again.  Was this the result of updates I may have installed recently?  Did something else change?  » Read more: VMWare HA – the wrong way.